This invention relates to double gong bells capable of generating a bell sound having composite tone colours therein.
A typical arrangement of a conventional bell is made of a single gong, a hammer for striking the gong surface to generate a bell sound, and a driving mechanism by which the hammer is actuated to move reciprocally against the gong surface: the driving mechanism being of the type in which either a motor drives a hammer through a transmission device or an electro-magnetic coil energizes directly a hammer to strike a gong.
This known bell has been found not entirely satisfactory in that the bell produces only a monotonous sound originating from an oscillation of the single gong whose natural resonance frequency is inherently determined by the material, shape, thickness or the like. As a result, the tone colour of the bell sound is fixed at a certain quality having a predetermined frequency and intensity, without substantially changing sound waveshape or envelope.